Puppy fat jabs: are our pets next in line for weight-loss drugs?

The Guardian

15 hours ago

Where humans lead, their dogs tend to follow – now it seems that might even apply to weight-loss wonder drugs.
Medications such as Wegovy have become ubiquitous among people hoping to shed pounds quickly. But businesses keen to cash in on the science behind the weight-loss jabs are now investigating other applications for the drugs, and our four-legged friends could be the next in line for a slimming solution.
The active ingredients in the drugs mimic a hormone called GLP-1, which makes people want to eat less. One biotech firm has just announced trials for an implant that reproduces the effect in dogs, with the aim of bringing it to the market as soon as 2028.
The hope is that the same science can be used to quell the voracious appetite of some dog breeds that can lead to them piling on the pounds.
While experts say such medications could be beneficial for some overweight animals, their use outside of humans is not without complication or the potential for controversy.
What is not contentious is that pet weight is a real issue for many owners.
Neutering, age, a lack of activity and overfeeding are among the factors that can contribute to the problem. According to a 2024 report by the trade body UK Pet Food, 50% of dogs and 43% of cats are overweight.
Excess weight can shorten the lifespan of pets and reduce their quality of life; tubby cats, for instance, face a greater risk of problems including diabetes, urinary tract issues and cancer, while overweight canines are more likely to have to contend with conditions such as arthritis, heart disease, breathing problems and cancer.
Commonly recommended solutions are increased exercise and strict prescription diets that are high in fibre and protein but low in calories.
Dr Eleanor Raffan, a veterinary surgeon and expert in canine genetics and obesity at the University of Cambridge, said some good old-fashioned discipline should be the first option.
'I would [advise] owners, both for the benefit of their pockets, and possibly for the benefit of their pets, to try modifying their dog's diet and exercise regime first, because I think we know that that can be safe and effective if done well,' she said.
'But if that fails, or if there's an urgent need to get weight loss, then I see no reason why using [GLP-1 mimic] drugs shouldn't be a reasonable option, so long as they are tested in proper, prospective, well-designed, randomised clinical trials before being widely offered in practice.'
A strong selling point of the medication is that it helps pet owners navigate one of the biggest obstacles to pet weight loss: what many vets describe as 'pester power', or, to put it another way, humans' inability to say no to their loyal companions.
'What our research shows in our group … is that that if you have a very foodie dog, you have to work much harder,' she said. 'You have to really resist the big brown eye treatment and that can be really hard in our busy lives today.'
Appetite suppressants may help stop the kind of begging that most pet owners are familiar with, but they come with one major drawback: that a pet's appetite is often an important marker of their health. Some experts worry that if humans are unable to tell if their animal has stopped eating because they are unwell or because the weight loss drugs are doing their job, it could prove dangerous.
'If cats stop eating for a few days, they can develop a condition called hepatic lipidosis and other problems, which can be life threatening,' said Raffan.
Michael Klotsman is the chief executive of Okava, one of the companies developing a long-acting implant called OKV-119 that contains a GLP-1 mimic called exenatide.
He said behavioural changes from OKV-119 were quite different from illness-related appetite loss.
'What owners should expect to see is their pet eating appropriate portions without the previous food obsession – they'll still eat regularly and show interest in meals, just without the excessive begging, scavenging or gulping behaviour,' he said.
The company is planning trials in dogs, and hopes to launch its implant commercially in 2028 or 2029.
Klotsman said: 'OKV-119 represents an additional tool for veterinarians treating pets where conventional approaches have been insufficient, similar to how GLP-1 therapies have provided new hope for human patients struggling with obesity despite their best efforts with diet and exercise.'
Prof Peter Sandøe, of the University of Copenhagen and the director of the Danish Centre for the Study of Companion Animal Welfare, said such drugs could potentially help some pets, such as food-obsessed dogs.
However, he added, if owners were concerned enough about their pet's weight to consider such medications, then there were many other – probably cheaper – options they could try, from activity feeders to extra walks, microchip-controlled feeders, and switching out treats for fun and games.
'Why take the medical solution if there's some other solutions that actually might be better for both human and animal welfare?' he said.